In the known art pointing devices are utilized in connection with computers, video game controls, hand held remote controls, web TV controls, consumer electronic controls, industrial controllers, medical equipment, automotive equipment and other similar applications. With such pointing devices, the user is allowed to readily control the speed and directional input and make selections within a particular application utilizing a single control. It is the objective of such pointing devices to provide a rapid and effortless means of control in an application and minimize fatigue and the amount of interrupted action required of the user.
Representative pointing devices of the known art and their shortcomings will now be described.
U.S. Pat. No. 4,352,084 to Graves et al discloses a variable resistor with a substrate that has various conductive and resistive regions for varied output. The drawback of such device being that it not capable of dual X-Y axis output.
U.S. Pat. No. 4,864,272 to Cecchi et al discloses a joystick controller utilizing a sliding contact on resistive and conductive regions that are parallel to one another and perpendicular to the center of the axis of movement. The drawback to this method of creating an output that may be interpreted into speed and direction, is that operational contact results in abrasion of the resistive and conductive regions as well as requiring many components to accomplish the variable resistive output.
U.S. Pat. No. 5,498,843 to Date et al discloses a pivoting digital only pointing device that makes contact in the direction of a direct axis. Date teaches the use of a single speed and eight directions. Date does not teach the use of resistive regions for variable speeds and increased variability of direction. The resultant drawback being that the Date device is limited in variability of speed and direction.
U.S. Pat. No. 4,896,003 to Hsieh discloses a pivoting pad, digital only, pointing device that makes contact in the direction of a direct axis. Hsieh also teaches the use of parallel conductive digital traces that extend perpendicularly from the center. The resultant drawback being that the Hsieh device is limited in its number of digital contacts due to congestion; thus, it is impractical to provide a device having a greatly variable number of speeds and directions.
U.S. Pat. No. 5,488,206 to Wu discloses the use of conductive rubber and membrane switches in a digital fashion to supply speed and directional output; and is therefore limited to providing a small number of speeds.
U.S. Pat. No. 5,376,913 to Pine et al discloses the use of a solid conductive curved disc and that a single resistor can be contacted to affect a change in resistance. The drawback to the Pine device being that, Pine does not anticipate the use multiple resistors for pointing or the use of just a segment of the conductive disc to minimize costs.
U.S. Pat. No. 5,675,309 to DeVolpi discloses the use of a continuous curved disc that pivots on a substrate that has resistive and conductive elements completely covering or surrounding the center of a printed circuit board in a continuous 360 degree area. The drawbacks to the DeVolpi device being that directions other than the true axis are hard to control for infinite controlled proportional resolution due to the footprint of the conductive rubber disc; and truly consistent varied angles cannot be achieved. Further, the solid conductive curved disc is the most expensive component of the disclosed technology.
Finally, U.S. Pat. No. 5,278,557 to Stokes et al discloses a force-sensitive variable resistor that operates using triangulation. The drawback to this method of providing a speed and direction output is that a polymer force-sensitive material is utilized, and the inherent properties of such a material result in having to apply excessive force to get an increased speed output, which in extended use can cause fatigue in the user. Accordingly it is the object of the present invention to provide an improved multi speed multi direction analog pad pointing device eliminating the shortcomings of the above identified known art, and which can be mass produced and assembled with consistent quality at a cost comparable to a conventional pointing device, requiring a reduced amount of effort in operation and having greater resolution and variability of speed and directional output.